I have not toured there but have travled there a few times. It doesnt look like a big deal to stealth camp and even if "caught" in the act I dont think anyone would care and there really is not a lot of crime or violence there. There are a lot of national parks with very cheap camping fees so if you plan carefully you might not even have to stealth. In Korea you can sleep in the bath houses but I hear you can only do that in some of the Japanese ones. If you can find out which ones let you sleep there you would have a low cost hotel. If your on a tight budget though.... just come to Korea